Glossary by "L"

Least-cost planning

See:Integrated resources planning

Source: ESA Technical Working Group

346

Levelized cost

See:Levelized cost of energy

Source: ESA Technical Working Group

347

Levelized cost of energy

Acronym(s): LCOE

A common metric used to compare the “levelized” or “annuity equivalent” cost per unit to generate electric energy, over a specified period (number of years), given assumed cost-of-capital, start year prices and cost/price escalation rates. The two primary components are 1) capital plant and equipment related cost and 2) expense related costs such as maintenance and fuel.
Importantly, LCOE is used to make comparisons between generation alternatives assuming comparable bases. So they reflect relative cost—and are unlikely to reflect actual cost—for a specific alternative or circumstance.

Source: ESA Technical Working Group

348

Life extension

Actions taken to extend the useful life of utility equipment, primarily by reducing peak demand served by the equipment. For most equipment types that involves reducing the equipment’s maximum and on-peak operating temperatures. For underground power cables a key result is reduced ground faults.

Source: ESA Technical Working Group

349

Limiting element

The element within a “system” that: 1) is operating at its appropriate rating or 2) would be following the limiting contingency. Thus, the limiting element establishes a system limit.

Line fault

See:Fault

Source: ESA Technical Working Group

351

Load

An end-use device or an end-use customer receiving electric power and using electric energy from the electrical system (grid). Note: The term load is sometimes treated as a synonym for demand, which is the measure of power that a load receives or requires.

Source: ESA Technical Working Group

352

Load center

A specific geographical area where electric load is concentrated, especially areas within a utility’s service area where demand is highest.

Source: ESA Technical Working Group

353

Load management

See:Demand side management

Source: ESA Technical Working Group

354

Load shape

A graphical representation of electric demand over time.

Source: ESA Technical Working Group

356

Load-serving entities

Acronym(s): LSE

Utilities, marketers or aggregators who provide electric power to a large number of end-use customers.

Local publicly owned electric utilities

A municipal corporation, a municipal utility district, an irrigation district or a joint power authority (which can include one or more of the agencies mentioned above) furnishing electric services over its own transmission facilities, or furnishing electric service over its own or its members

Locational marginal price

Acronym(s): LMP

A method of setting prices in an ISO market whereby prices at specific locations on the grid are determined by the marginal price of generation of power available to that specific location. Prices vary from location-to-location based on transmission congestion and losses.